How to Merge gif and image

[rickk]

(01-13-2023, 09:33 AM)rich2005 Wrote:
Unless you do all by hand one-layer at a time you need a script to merge the background layer with each layer of the animation.

A funny thing happened to me on the way to the office today. 

I was going through the motions of this thread,  as I often do, just trying to expand my horizons

And opened a 800x600 png image, and then opened as layers a 480x368  20 frame gif, and then went to Filters>Animation and selected "unoptimize" from the menu.....and Gimp added the base .png image to each and every of the 20 animation layer---no script required  All I had to do was merge the original "background" layer of the original gif down into the base .png below it in the stack......and I was good to go.  the resulting file exported equally well in either "replace" or "combine" mode as an animated gif

The reason I even mention this, is because it was a lot easier than fiddling with a script.  Am I missing something?



This got me to thinking. I opened another copy of the original png file, and then opened as layers the  20 frame gif, again merging the gif background layer into the png below it in the stack, and then exported it in "combine" mode as an animated gif

no other processing.....and it seems to run equally well. But again, am I missing something? the solution  seems on the surface almost too simple. 

One caveat seems to be that the gif itself must not be optimized to begin with.

Do you see any down side to what I'm doing with this?

thanks in advance